Particle jets driven by the central explosion determine the dispersal of particles in the blast flow. We tracked the dynamic fragmentation of sand shells with different saturation subject to the central explosion, and obtained the onset of jet formation and the characteristics of jets. The stretch and dissolution of particle jets can be studied by virtue of the analysis of the vibration acceleration of targets generated by the impact of jets. We found the interstitial fluid plays an important role in both formation and evolvement of particle jets.